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# pylint: disable=import-outside-toplevel

from typing import List, Optional

from pytest_mock import MockFixture
from sqlalchemy.engine.reflection import Inspector


def test_get_metrics(mocker: MockFixture) -> None:
    """
    Tests for ``get_metrics``.
    """
    from superset.db_engine_specs.base import MetricType
    from superset.db_engine_specs.sqlite import SqliteEngineSpec
    from superset.models.core import Database

    database = Database(database_name="my_database", sqlalchemy_uri="sqlite://")
    assert database.get_metrics("table") == [
        {
            "expression": "COUNT(*)",
            "metric_name": "count",
            "metric_type": "count",
            "verbose_name": "COUNT(*)",
        }
    ]

    class CustomSqliteEngineSpec(SqliteEngineSpec):
        @classmethod
        def get_metrics(
            cls,
            database: Database,
            inspector: Inspector,
            table_name: str,
            schema: Optional[str],
        ) -> List[MetricType]:
            return [
                {
                    "expression": "COUNT(DISTINCT user_id)",
                    "metric_name": "count_distinct_user_id",
                    "metric_type": "count_distinct",
                    "verbose_name": "COUNT(DISTINCT user_id)",
                },
            ]

    database.get_db_engine_spec_for_backend = mocker.MagicMock(  # type: ignore
        return_value=CustomSqliteEngineSpec
    )
    assert database.get_metrics("table") == [
        {
            "expression": "COUNT(DISTINCT user_id)",
            "metric_name": "count_distinct_user_id",
            "metric_type": "count_distinct",
            "verbose_name": "COUNT(DISTINCT user_id)",
        },
    ]